Clinical trials number

Physicians report that they participate in clinical research mostly because it is scientifically rewarding, but they are also attracted to the financial rewards and the opportunities to improve patient care (Lamberti, 2005). With clinical trials numbering in the tens of thousands, there is industry-wide concern that there may be a 15% shortfall in the number of qualified US investigators in the next few years (Zisson, 2001). There are several factors contributing to this dilemma. 

Clinical trials for r-IEN-y in RA indicated that the dmg is well tolerated (52). Consistent improvement in tender and swollen joint scores was observed, but a large number of patients were needed in the trial to show statistical significance for r-IEN-y treatment. In certain individuals, responses were remarkable. An additive effect between r-IEN-y and penicillamine was detected. Efficacy was lower when r-IEN-y was combined with gold therapy. Research is continuing. 

There has been a rebirth of interest in a spirin between the 1970s and 1990s as evidence accumulated from a number of clinical trials that aspirin ingestion lowers the incidence of myocardial infarction (39,40), unstable angina (41,42), and stroke (43). 

A large number of molecules have provided experimental evidence of neuroprotection in in vitro and in vivo models of Parkinson s disease and many of these putative neuroprotective substances are now the objects of clinical trials. Recently, a team of experts has identified potential neuroprotective agents to be tested in pilot studies [4]. Twelve compounds have been considered for clinical trials caffeine, coenzyme Q 10, creatine, estrogen, GPI1485, GM-1 ganglioside, minocycline, nicotine, pramipexole, ropinirol, rasagiline, and selegiline (for individual discussion see [4]). 

The number of clinical trials ongoing represents a growing interest in antisense technology. 

A number of different low molecular weight compounds are known to stablize proteins in their native conformation and, therefore, may be effective in correcting of protein folding abnormalities in vivo. Relevant compounds are iV-acetyl-L-lysine, L-camitine, taurine, betaine, ectoine, and hydroxy-ectoine [4]. Some of these chemical chaperones and pharmacological chaperones are already used in clinical trials to combat protein folding diseases, such as cystic fibrosis. 

However, already in an early clinical trial, rofecoxib was found to produce four times the number of myocardial infarctions than its comparator drug, naproxen. A subsequent trial of rofecoxib compared to placebo in colorectal cancer prevention demonstrated, after 18 months of study, that a greater number of myocardial infarctions occulted in the rofecoxib group. In 2004 the manufacturers of rofecoxib withdrew the diug from the market. A similar study of celecoxib compared to placebo in cancer prevention, showed that celecoxib also increased the risk of cardiovascular embolisms [3]. 

A large and rapidly growing number of clinical trials (phase I and phase II) evaluating the potential of DNA vaccines to treat and prevent a variety of human diseases are currently being performed ( http // clinicaltrials.gov) however, there is yet no licensed DNA vaccine product available for use in humans. The clinical trials include the treatment of various types of cancers (e.g., melanoma, breast, renal, lymphoma, prostate, and pancreas) and also the prevention and therapy of infectious diseases (e.g., HIV/ABDS, malaria, Hepatitis B vims, Influenza vims, and Dengue vims). So far, no principally adverse effects have been reported from these trials. The main challenge for the development of DNA vaccines for use in humans is to improve the rather weak potency. DNA vaccines are already commercially available for veterinary medicine for prevention of West Nile Vims infections in horses and Infectious Hematopoetic Necrosis Vims in Salmon. 

A number of rationally designed MMP inhibitors have shown some promise in the treatment of pathologies, which MMPs are suspected to be involved in. However, most of these, such as Marimastat (BB-2516), a broad spectrum MMP inhibitor, or trocade (Ro 32-3555), an MMP-1 selective inhibitor, have performed poorly in clinical trials. The failure of Marimastat was partially responsible for the folding of British Biotech, which developed it. The failure of... 

---